US5271368A - Fuel control system for engine - Google Patents

Fuel control system for engine Download PDF

Info

Publication number
US5271368A
US5271368A US08/043,846 US4384693A US5271368A US 5271368 A US5271368 A US 5271368A US 4384693 A US4384693 A US 4384693A US 5271368 A US5271368 A US 5271368A
Authority
US
United States
Prior art keywords
engine
engine speed
detecting means
detects
accessory
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US08/043,846
Inventor
Masaki Fujii
Shigetoshi Kawano
Hideki Kobayashi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mazda Motor Corp
Original Assignee
Mazda Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mazda Motor Corp filed Critical Mazda Motor Corp
Assigned to MAZDA MOTOR CORPORATION reassignment MAZDA MOTOR CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FUJII, MASAKI, KAWANO, SHIGETOSHI, KOBAYASHI, HIDEKI
Application granted granted Critical
Publication of US5271368A publication Critical patent/US5271368A/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/04—Introducing corrections for particular operating conditions
    • F02D41/12—Introducing corrections for particular operating conditions for deceleration
    • F02D41/123—Introducing corrections for particular operating conditions for deceleration the fuel injection being cut-off
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
    • F02D2200/101—Engine speed

Definitions

  • This invention relates to a fuel control system for an engine, and more particularly to a fuel control system for an engine in which fuel supply to the engine is cut during deceleration at different engine speeds depending on whether or not an accessory mechanism such as an air conditioner is operating.
  • the primary object of the present invention is to provide a fuel control system for an engine in which torque shock which is caused when the state of an accessory mechanism changes simultaneously with initiation of fuel cut can be avoided.
  • a fuel control system for an engine having an accessory mechanism driven by the engine comprising an accessory state detecting means which detects whether the accessory mechanism is operating, a deceleration detecting means which detects that the engine is decelerating, an engine speed detecting means which detects the engine speed, a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed, a preset engine speed changing means which increases the value of the preset engine speed when the accessory state detecting means detects that the accessory mechanism is operating, and an inhibiting means which inhibits the preset engine speed changing means from changing the value of the preset engine speed when the state of the accessory mechanism changes while the engine is decelerating.
  • a fuel control system for an engine having an accessory mechanism driven by the engine comprising an accessory state detecting means which detects whether the accessory mechanism is operating, a deceleration detecting means which detects that the engine is decelerating, an engine speed detecting means which detects the engine speed, a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed, a preset value setting means which sets the preset engine speed to a first value when the accessory state detecting means detects that the accessory mechanism is operating and to a second value lower than the first value when the accessory state detecting means detects that the accessory mechanism is not operating, and an inhibiting means which inhibits the preset value setting means from changing the value of the preset value when the state of the accessory mechanism changes while the engine is decelerating and at the same time the engine speed detected by the engine speed detecting means is between the
  • FIG. 1 is a schematic view showing a fuel control system in accordance with an embodiment of the present invention
  • FIG. 2 is a flow chart for illustrating the operation of the engine control unit
  • FIG. 3 is a view showing the relation between the present engine speed and the throttle opening
  • FIG. 4 is a flow chart for illustrating the operation of the engine control unit in another embodiment of the present invention.
  • an engine 1 has a combustion chamber 3 and a piston 2 slidably received in the combustion chamber 3.
  • Reference numeral 4 denotes an intake port provided with an intake valve 7 and reference numeral 6 denotes an exhaust port provided with an exhaust valve 8.
  • the intake port 4 is connected to an intake passage provided with a throttle valve 9 and a surge tank 10 downstream of the throttle valve 9.
  • a fuel injector 11 is provided in the intake passage downstream of the surge tank 10.
  • An airflow sensor 20a in an airflow meter 20 detects the amount of intake air introduced into the intake port 4.
  • An intake air temperature sensor 21 detects the temperature of intake air.
  • a throttle opening sensor 23 detects the opening of the throttle valve 9 and has an idle switch 22.
  • An engine speed sensor 25 detects the engine speed by way of a distributor 15.
  • An O 2 sensor 26 and a catalytic convertor 24 are provided in the exhaust port 6.
  • An engine control unit 30 receives signals from the sensors described above and ON/OFF signals from accessory mechanisms such as a compressor for an air conditioner, a pump for a power steering system and the like which are driven by the crankshaft of the engine by way of a belt, and controls the distributor 15 and the fuel injector 11.
  • the engine control unit 30 further controls an on-off valve 13 provided in a bypass intake passage 12.
  • the engine control unit 30 first determines whether the idle switch 22 is ON.
  • the idle switch 22 is turned on when the throttle valve 9 is full closed, that is, when the engine is decelerating. (step S1)
  • the engine control unit 30 determines whether the compressor for the air conditioner is driven by the engine (hereinafter referred to ON) (step S2).
  • step S3 determines in step S3 whether air conditioner flag FA (which is set to 1 when the air conditioner is turned on) is 0, and when it is determined that the air conditioner flag FA is 0, the engine control unit 30 directly proceeds to step S7 and otherwise proceeds to step S7 after setting the air conditioner flag FA to 0 in step S4. In step S7, the engine control unit 30 does not perform fuel cut.
  • air conditioner flag FA which is set to 1 when the air conditioner is turned on
  • step S2 When it is determined in step S2 that the air conditioner is ON, the engine control unit 30 determines in step S5 whether the air conditioner flag FA is 1, and when it is determined that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S7 and otherwise proceeds to step S7 after setting the air conditioner flag FA to 1 in step S6.
  • step S8 determines whether the air conditioner is ON.
  • step S9 determines whether the air conditioner flag FA is 1.
  • the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than a second preset value Ne2 which is lower than a first preset value Ne1 as shown in FIG. 3.
  • the engine control unit 30 determines in step S10 whether the engine speed Ne is higher than the second preset value Ne2, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S11 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S7.
  • step S9 when it is determined in step S9 that the air conditioner flag FA is 1, which means that the air conditioner has changed from the operating state to the inoperative state after the idle switch was turned on, the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than the first preset value Ne1. That is, the engine control unit 30 determines in step S12 whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S11 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S7.
  • step S8 When it is determined in step S8 that the air conditioner is ON, the engine control unit 30 determines in step S13 whether the air conditioner flag FA is 1. When it is determined in step S13 that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S12 and otherwise the engine control unit 30 proceeds to step S12 after setting the air conditioner frag FA to 1 in step S14. In step S12, the engine control unit 30 determines whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S11 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S7.
  • whether fuel cut is to be performed during deceleration of the engine is determined on the basis of whether the engine speed is higher than the first preset value Ne1 which is higher than the second preset value Ne2 when the air conditioner is on and on the basis of whether the engine speed is higher than the second preset value Ne2 when the air conditioner is off though the determination is made on the basis of the first preset value Ne1 when the air conditioner is turned off during the deceleration of the engine.
  • the engine control unit 30 first determines whether the idle switch 22 is ON. (step S21) When it is determined than the idle switch 22 is not ON, the engine control unit 30 determines whether the air conditioner is ON. (step S22) When it is determined that the air conditioner is not ON, the engine control unit 30 determines in step S23 whether air conditioner flag FA is 0, and when it is determined that the air conditioner flag FA is 0, the engine control unit 30 directly proceeds to step S27 and otherwise proceeds to step S27 after setting the air conditioner flag FA to 0 in step S24. In step S27, the engine control unit 30 does not perform fuel cut.
  • step S22 When it is determined in step S22 that the air conditioner is ON, the engine control unit 30 determines in step S25 whether the air conditioner flag FA is 1, and when it is determined that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S27 and otherwise proceeds to step S27 after setting the air conditioner flag FA to 1 in step S26.
  • step S28 determines in step S28 whether the air conditioner is ON.
  • step S29 determines in step S29 whether the air conditioner flag FA is 1.
  • the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than a second preset value Ne2 which is lower than a first preset value Ne1.
  • the engine control unit 30 determines in step S30 whether the engine speed Ne is higher than the second preset value Ne2, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S31 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S27.
  • step S29 when it is determined in step S29 that the air conditioner flag FA is 1, which means that the air conditioner has changed from the operating state to the inoperative state after the idle switch was turned on, the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than the first preset value Ne1. That is, the engine control unit 30 determines in step S32 whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S31 after setting the air conditioner flag FA to 0 in step S33 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S27.
  • step S34 determines in step S34 whether the air conditioner flag FA is 1.
  • the engine control unit 30 directly proceeds to step S35 and otherwise the engine control unit 30 proceeds to step S35 after setting the air conditioner flag FA to 1 in step S36.
  • step S35 the engine control unit 30 determines whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S31 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S27.
  • whether fuel cut is to be performed during deceleration of the engine is determined on the basis of whether the engine speed is higher than the first preset value Ne1 which is higher than the second preset value Ne2 when the air conditioner is on and on the basis of whether the engine speed is higher than the second preset value Ne2 when the air conditioner is off though the determination is made on the basis of the first preset value Ne1 when the air conditioner is turned off during the deceleration of the engine and the engine speed is between the first and second preset values.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Control Of Vehicle Engines Or Engines For Specific Uses (AREA)

Abstract

In a fuel control system of an engine having an air conditioner driven by the engine, fuel supply is cut during deceleration of the engine when the engine speed is higher than a first preset value with the air conditioner on and when the engine speed is higher than a second preset value with the air conditioner off, the first preset value being higher than the second preset value. When the air conditioner is turned off during the deceleration of the engine, fuel supply is cut when the engine speed is higher than the first preset value, and when the air conditioner is turned on during the deceleration of the engine, fuel supply is cut when the engine speed is higher than the second preset value.

Description

BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a fuel control system for an engine, and more particularly to a fuel control system for an engine in which fuel supply to the engine is cut during deceleration at different engine speeds depending on whether or not an accessory mechanism such as an air conditioner is operating.
2. Description of the Prior Art
There has been known a fuel control system in which it is determined that the engine is decelerating and fuel supply to the engine is cut when the throttle valve is full closed and the engine speed is not lower than a preset speed in order to improve fuel economy and clean the engine emission. When an accessory mechanism such as an air conditioner is operating, the preset speed is set higher than when the accessory mechanism is not operating, thereby preventing hunting and engine stall.
However, in the conventional fuel control system, there has been a problem that when, for instance, the air conditioner is turned off while the engine is decelerating, that is, when the air conditioner changes from the operating state to the inoperative state while the engine is decelerating, toque shock occurs due to reduction in the engine load and shock occurs due to initiation of fuel cut, which causes uncomfortable vibration of the vehicle body.
SUMMARY OF THE INVENTION
In view of the foregoing observations and description, the primary object of the present invention is to provide a fuel control system for an engine in which torque shock which is caused when the state of an accessory mechanism changes simultaneously with initiation of fuel cut can be avoided.
In accordance with one aspect of the present invention, there is provided a fuel control system for an engine having an accessory mechanism driven by the engine comprising an accessory state detecting means which detects whether the accessory mechanism is operating, a deceleration detecting means which detects that the engine is decelerating, an engine speed detecting means which detects the engine speed, a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed, a preset engine speed changing means which increases the value of the preset engine speed when the accessory state detecting means detects that the accessory mechanism is operating, and an inhibiting means which inhibits the preset engine speed changing means from changing the value of the preset engine speed when the state of the accessory mechanism changes while the engine is decelerating.
In accordance with another aspect of the present invention, there is provided a fuel control system for an engine having an accessory mechanism driven by the engine comprising an accessory state detecting means which detects whether the accessory mechanism is operating, a deceleration detecting means which detects that the engine is decelerating, an engine speed detecting means which detects the engine speed, a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed, a preset value setting means which sets the preset engine speed to a first value when the accessory state detecting means detects that the accessory mechanism is operating and to a second value lower than the first value when the accessory state detecting means detects that the accessory mechanism is not operating, and an inhibiting means which inhibits the preset value setting means from changing the value of the preset value when the state of the accessory mechanism changes while the engine is decelerating and at the same time the engine speed detected by the engine speed detecting means is between the first and second values of the preset engine speed.
With these arrangements, torque shocks caused by turning off the accessory mechanism and caused by fuel cut cannot synchronize with each other to enhance the shock.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing a fuel control system in accordance with an embodiment of the present invention,
FIG. 2 is a flow chart for illustrating the operation of the engine control unit,
FIG. 3 is a view showing the relation between the present engine speed and the throttle opening, and
FIG. 4 is a flow chart for illustrating the operation of the engine control unit in another embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, an engine 1 has a combustion chamber 3 and a piston 2 slidably received in the combustion chamber 3. Reference numeral 4 denotes an intake port provided with an intake valve 7 and reference numeral 6 denotes an exhaust port provided with an exhaust valve 8.
The intake port 4 is connected to an intake passage provided with a throttle valve 9 and a surge tank 10 downstream of the throttle valve 9. A fuel injector 11 is provided in the intake passage downstream of the surge tank 10. An airflow sensor 20a in an airflow meter 20 detects the amount of intake air introduced into the intake port 4. An intake air temperature sensor 21 detects the temperature of intake air. A throttle opening sensor 23 detects the opening of the throttle valve 9 and has an idle switch 22. An engine speed sensor 25 detects the engine speed by way of a distributor 15. An O2 sensor 26 and a catalytic convertor 24 are provided in the exhaust port 6.
An engine control unit 30 receives signals from the sensors described above and ON/OFF signals from accessory mechanisms such as a compressor for an air conditioner, a pump for a power steering system and the like which are driven by the crankshaft of the engine by way of a belt, and controls the distributor 15 and the fuel injector 11. The engine control unit 30 further controls an on-off valve 13 provided in a bypass intake passage 12.
The operation of the engine control unit 30 will be described with reference to the flow chart shown in FIG. 2, hereinbelow.
The engine control unit 30 first determines whether the idle switch 22 is ON. The idle switch 22 is turned on when the throttle valve 9 is full closed, that is, when the engine is decelerating. (step S1) When it is determined than the idle switch 22 is not ON, the engine control unit 30 determines whether the compressor for the air conditioner is driven by the engine (hereinafter referred to ON) (step S2). When it is determined that the compressor for the air conditioner is not driven by the engine (hereinafter referred to not ON), the engine control unit 30 determines in step S3 whether air conditioner flag FA (which is set to 1 when the air conditioner is turned on) is 0, and when it is determined that the air conditioner flag FA is 0, the engine control unit 30 directly proceeds to step S7 and otherwise proceeds to step S7 after setting the air conditioner flag FA to 0 in step S4. In step S7, the engine control unit 30 does not perform fuel cut. When it is determined in step S2 that the air conditioner is ON, the engine control unit 30 determines in step S5 whether the air conditioner flag FA is 1, and when it is determined that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S7 and otherwise proceeds to step S7 after setting the air conditioner flag FA to 1 in step S6.
When it is determined in step S1 that the idle switch 22 is ON, the engine control unit 30 determines in step S8 whether the air conditioner is ON. When it is determined that the air conditioner is not ON, the engine control unit 30 determines in step S9 whether the air conditioner flag FA is 1. When it is determined in step S9 that the air conditioner flag FA is not 1, which means that the air conditioner has been OFF from before the idle switch 22 was turned on, the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than a second preset value Ne2 which is lower than a first preset value Ne1 as shown in FIG. 3. That is, the engine control unit 30 determines in step S10 whether the engine speed Ne is higher than the second preset value Ne2, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S11 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S7.
On the other hand, when it is determined in step S9 that the air conditioner flag FA is 1, which means that the air conditioner has changed from the operating state to the inoperative state after the idle switch was turned on, the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than the first preset value Ne1. That is, the engine control unit 30 determines in step S12 whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S11 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S7.
When it is determined in step S8 that the air conditioner is ON, the engine control unit 30 determines in step S13 whether the air conditioner flag FA is 1. When it is determined in step S13 that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S12 and otherwise the engine control unit 30 proceeds to step S12 after setting the air conditioner frag FA to 1 in step S14. In step S12, the engine control unit 30 determines whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S11 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S7.
As can be understood from the description above, in this embodiment, whether fuel cut is to be performed during deceleration of the engine is determined on the basis of whether the engine speed is higher than the first preset value Ne1 which is higher than the second preset value Ne2 when the air conditioner is on and on the basis of whether the engine speed is higher than the second preset value Ne2 when the air conditioner is off though the determination is made on the basis of the first preset value Ne1 when the air conditioner is turned off during the deceleration of the engine.
The operation of the engine control unit 30 in another embodiment of the present invention will be described with reference to the flow chart shown in FIG. 4, hereinbelow.
The engine control unit 30 first determines whether the idle switch 22 is ON. (step S21) When it is determined than the idle switch 22 is not ON, the engine control unit 30 determines whether the air conditioner is ON. (step S22) When it is determined that the air conditioner is not ON, the engine control unit 30 determines in step S23 whether air conditioner flag FA is 0, and when it is determined that the air conditioner flag FA is 0, the engine control unit 30 directly proceeds to step S27 and otherwise proceeds to step S27 after setting the air conditioner flag FA to 0 in step S24. In step S27, the engine control unit 30 does not perform fuel cut.
When it is determined in step S22 that the air conditioner is ON, the engine control unit 30 determines in step S25 whether the air conditioner flag FA is 1, and when it is determined that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S27 and otherwise proceeds to step S27 after setting the air conditioner flag FA to 1 in step S26.
When it is determined in step S21 that the idle switch 22 is ON, the engine control unit 30 determines in step S28 whether the air conditioner is ON. When it is determined that the air conditioner is not ON, the engine control unit 30 determines in step S29 whether the air conditioner flag FA is 1. When it is determined in step S29 that the air conditioner flag FA is not 1, which means that the air conditioner has been OFF from before the idle switch 22 was turned on, the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than a second preset value Ne2 which is lower than a first preset value Ne1. That is, the engine control unit 30 determines in step S30 whether the engine speed Ne is higher than the second preset value Ne2, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S31 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S27.
On the other hand, when it is determined in step S29 that the air conditioner flag FA is 1, which means that the air conditioner has changed from the operating state to the inoperative state after the idle switch was turned on, the engine control unit 30 determines whether fuel cut is to be performed on the basis of whether the engine speed Ne is higher than the first preset value Ne1. That is, the engine control unit 30 determines in step S32 whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S31 after setting the air conditioner flag FA to 0 in step S33 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S27.
When it is determined in step S28 that the air conditioner is ON, the engine control unit 30 determines in step S34 whether the air conditioner flag FA is 1. When it is determined in step S34 that the air conditioner flag FA is 1, the engine control unit 30 directly proceeds to step S35 and otherwise the engine control unit 30 proceeds to step S35 after setting the air conditioner flag FA to 1 in step S36. In step S35, the engine control unit 30 determines whether the engine speed Ne is higher than the first preset value Ne1, and when it is determined that the former is higher than the latter, the engine control unit 30 proceeds to step S31 and performs fuel cut, and otherwise the engine control unit 30 proceeds to step S27.
As can be understood from the description above, in this embodiment, whether fuel cut is to be performed during deceleration of the engine is determined on the basis of whether the engine speed is higher than the first preset value Ne1 which is higher than the second preset value Ne2 when the air conditioner is on and on the basis of whether the engine speed is higher than the second preset value Ne2 when the air conditioner is off though the determination is made on the basis of the first preset value Ne1 when the air conditioner is turned off during the deceleration of the engine and the engine speed is between the first and second preset values.

Claims (7)

What is claimed is;
1. A fuel control system for an engine having an accessory mechanism driven by the engine comprising
an accessory state detecting means which detects whether the accessory mechanism is operating,
a deceleration detecting means which detects that the engine is decelerating,
an engine speed detecting means which detects the engine speed,
a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed,
a preset engine speed changing means which increases the value of the preset engine speed when the accessory state detecting means detects that the accessory mechanism is operating, and
an inhibiting means which inhibits the preset engine speed changing means from changing the value of the preset engine speed when the state of the accessory mechanism changes while the engine is decelerating.
2. A fuel control system as defined in claim 1 in which said deceleration detecting means determines that the engine is decelerating when the throttle valve of the engine is full closed.
3. A fuel control system as defined in claim 1 in which said accessory mechanism is an air conditioner.
4. A fuel control system for an engine having an accessory mechanism driven by the engine comprising
an accessory state detecting means which detects whether the accessory mechanism is operating,
a deceleration detecting means which detects that the engine is decelerating,
an engine speed detecting means which detects the engine speed,
a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed,
a preset value setting means which sets the preset engine speed to a first value when the accessory state detecting means detects that the accessory mechanism is operating and to a second value lower than the first value when the accessory state detecting means detects that the accessory mechanism is not operating, and
an inhibiting means which inhibits the preset value setting means from changing the value of the preset value when the state of the accessory mechanism changes while the engine is decelerating and at the same time the engine speed detected by the engine speed detecting means is between the first and second values of the preset engine speed.
5. A fuel control system as defined in claim 4 in which said deceleration detecting means determines that the engine is decelerating when the throttle valve of the engine is full closed.
6. A fuel control system as defined in claim 4 in which said accessory mechanism is an air conditioner.
7. A fuel control system for an engine having an accessory mechanism driven by the engine comprising
an accessory state detecting means which detects whether the accessory mechanism is operating,
a deceleration detecting means which detects that the engine is decelerating,
an engine speed detecting means which detects the engine speed,
a fuel cut means which cuts fuel supply to the engine when the deceleration detecting means detects that the engine is decelerating and the engine speed detected by the engine speed detecting means is higher than a preset engine speed, and
a preset value setting means which sets the preset engine speed to a first value when the accessory state detecting means detects that the accessory mechanism is operating and to a second value lower than the first value when the accessory state detecting means detects that the accessory mechanism is not operating while the engine is not decelerating.
US08/043,846 1992-04-09 1993-04-07 Fuel control system for engine Expired - Fee Related US5271368A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP04088824A JP3093861B2 (en) 1992-04-09 1992-04-09 Engine fuel control device
JP4-088824 1992-04-09

Publications (1)

Publication Number Publication Date
US5271368A true US5271368A (en) 1993-12-21

Family

ID=13953684

Family Applications (1)

Application Number Title Priority Date Filing Date
US08/043,846 Expired - Fee Related US5271368A (en) 1992-04-09 1993-04-07 Fuel control system for engine

Country Status (3)

Country Link
US (1) US5271368A (en)
JP (1) JP3093861B2 (en)
KR (1) KR0132772B1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5387163A (en) * 1992-05-27 1995-02-07 Sanshin Kogyo Kabushiki Kaisha Vertical type multi-cylinder internal combustion engine
US5546755A (en) * 1995-03-07 1996-08-20 Krieger; Todd N. Automatic air conditioner shutoff system
US6434453B1 (en) * 1999-03-09 2002-08-13 Honda Giken Kogyo Kabushiki Kaisha Engine control system for hybrid vehicle
US20120318015A1 (en) * 2011-06-14 2012-12-20 Nissan Motor Co., Ltd. Vehicle air conditioner control system
US20120324929A1 (en) * 2011-06-21 2012-12-27 Nissan Motor Co., Ltd. Vehicle air-conditioner control system
US9221451B2 (en) 2012-05-17 2015-12-29 Toyota Motor Engineering & Manufacturing North America, Inc. Systems and methods for increasing fuel efficiency
US20210071599A1 (en) * 2019-09-10 2021-03-11 Ford Global Technologies, Llc Systems and methods for controlling purge flow from a vehicle fuel vapor storage canister

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5534295A (en) * 1978-08-31 1980-03-10 Bayer Ag Novel cationic dyestuff*its manufacture and use
US4510902A (en) * 1982-04-06 1985-04-16 Mazda Motor Corporation Fuel supply control in deceleration of an internal combustion engine for vehicles
US4510901A (en) * 1982-03-17 1985-04-16 Honda Giken Kogyo Kabushiki Kaisha Throttle valve control apparatus
US4581924A (en) * 1984-05-25 1986-04-15 Honda Giken Kogyo K.K. Method of detecting opening of a throttle valve in a fully closed position in an internal combustion engine
US4694796A (en) * 1985-05-10 1987-09-22 Nissan Motor Company, Limited System and method for controlling fuel supply to a vehicular internal combustion engine with fuel supply cutoff function
US4729354A (en) * 1986-03-05 1988-03-08 Mazda Motor Corporation Fuel supply control system for use in engine
US4730587A (en) * 1984-05-07 1988-03-15 Kazuhiko Norota Control device of an internal combustion engine
US4790275A (en) * 1987-01-27 1988-12-13 Mazda Motor Corporation Fuel supply cut-off control system for engine of an automotive vehicle
US4860211A (en) * 1986-05-29 1989-08-22 Nissan Motor Co., Ltd. Air fuel ratio control apparatus

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5534295A (en) * 1978-08-31 1980-03-10 Bayer Ag Novel cationic dyestuff*its manufacture and use
US4510901A (en) * 1982-03-17 1985-04-16 Honda Giken Kogyo Kabushiki Kaisha Throttle valve control apparatus
US4510902A (en) * 1982-04-06 1985-04-16 Mazda Motor Corporation Fuel supply control in deceleration of an internal combustion engine for vehicles
US4730587A (en) * 1984-05-07 1988-03-15 Kazuhiko Norota Control device of an internal combustion engine
US4581924A (en) * 1984-05-25 1986-04-15 Honda Giken Kogyo K.K. Method of detecting opening of a throttle valve in a fully closed position in an internal combustion engine
US4694796A (en) * 1985-05-10 1987-09-22 Nissan Motor Company, Limited System and method for controlling fuel supply to a vehicular internal combustion engine with fuel supply cutoff function
US4729354A (en) * 1986-03-05 1988-03-08 Mazda Motor Corporation Fuel supply control system for use in engine
US4860211A (en) * 1986-05-29 1989-08-22 Nissan Motor Co., Ltd. Air fuel ratio control apparatus
US4790275A (en) * 1987-01-27 1988-12-13 Mazda Motor Corporation Fuel supply cut-off control system for engine of an automotive vehicle

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5387163A (en) * 1992-05-27 1995-02-07 Sanshin Kogyo Kabushiki Kaisha Vertical type multi-cylinder internal combustion engine
US5546755A (en) * 1995-03-07 1996-08-20 Krieger; Todd N. Automatic air conditioner shutoff system
US6434453B1 (en) * 1999-03-09 2002-08-13 Honda Giken Kogyo Kabushiki Kaisha Engine control system for hybrid vehicle
US20120318015A1 (en) * 2011-06-14 2012-12-20 Nissan Motor Co., Ltd. Vehicle air conditioner control system
US9259992B2 (en) * 2011-06-14 2016-02-16 Nissan Motor Co., Ltd. Vehicle air conditioner control system
US20120324929A1 (en) * 2011-06-21 2012-12-27 Nissan Motor Co., Ltd. Vehicle air-conditioner control system
US9102213B2 (en) * 2011-06-21 2015-08-11 Nissan Motor Co., Ltd. Vehicle air-conditioner control system and fuel supply cut-off
US9221451B2 (en) 2012-05-17 2015-12-29 Toyota Motor Engineering & Manufacturing North America, Inc. Systems and methods for increasing fuel efficiency
US20210071599A1 (en) * 2019-09-10 2021-03-11 Ford Global Technologies, Llc Systems and methods for controlling purge flow from a vehicle fuel vapor storage canister
US11008963B2 (en) * 2019-09-10 2021-05-18 Ford Global Technologies, Llc Systems and methods for controlling purge flow from a vehicle fuel vapor storage canister

Also Published As

Publication number Publication date
KR930021931A (en) 1993-11-23
JP3093861B2 (en) 2000-10-03
JPH05288103A (en) 1993-11-02
KR0132772B1 (en) 1998-04-15

Similar Documents

Publication Publication Date Title
US5492100A (en) Fuel control device for engine having disconnectable groups of cylinders
US5496228A (en) Evaporated fuel control system for an internal combustion engine responsive to torque reduction during shifting
US5357928A (en) Fuel injection control system for use in an internal combustion engine
US5261368A (en) Apparatus and method for controlling an internal combustion engine
US5271368A (en) Fuel control system for engine
US5291965A (en) Engine output control system for vehicle
US5213076A (en) Apparatus and method for controlling an internal combustion engine
EP0807751B1 (en) Idling control apparatus of internal combustion engine
US6173696B1 (en) Virtual power steering switch
US5027609A (en) Engine control system
JPH022458B2 (en)
US5027782A (en) Fuel control system for an automobile engine
US5765526A (en) Fuel supply control system for internal combustion engines
JPH0749073A (en) Control device for engine
US5445131A (en) Fuel control system for engine
JP2714062B2 (en) Engine ignition timing control device
JP3852633B2 (en) Engine deceleration control device
JPH05272395A (en) Fuel injection control device for internal combustion engine
JPH11107824A (en) Controller for engine
JPH0544531A (en) Control device for internal combustion engine
JPH11125139A (en) Intake amount control device for engine
JPH0460145A (en) Idle speed control device of engine
JPH0617655A (en) Exhaust gas purifying device of diesel engine
JPS63109260A (en) Overheat preventive device for car engine
JPS5965531A (en) Engine speed control device for internal-combustion engine

Legal Events

Date Code Title Description
AS Assignment

Owner name: MAZDA MOTOR CORPORATION, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FUJII, MASAKI;KAWANO, SHIGETOSHI;KOBAYASHI, HIDEKI;REEL/FRAME:006525/0665

Effective date: 19930402

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FPAY Fee payment

Year of fee payment: 4

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20011221